1. Field of the Invention
The present invention relates to a nozzle for dispensing paste-like or semi-liquid substances from a flexible dispensing tube or container. More particularly, this invention relates to a nozzle wherein the discharge of the paste-like or semi-liquid substance from the nozzle is selectively terminated without the nozzle contacting the surface upon which the substance has been discharged, and without undesired accumulation of the substance at the discharge portion of the nozzle.
2. Description of the Prior Art
The discharge of fluids from dispensing tubes, containers, or similar devices, is substantially controlled by the configuration of the discharge opening or spout through which the discharge fluid flows. To obtain a desired characteristic of fluid discharge, a nozzle is often added to the discharge opening or spout to alter the characteristics of the fluid flow. These nozzles control such features as the rate and shape of fluid flow, and the termination or cut off of dispensing.
Patents relating to nozzles for controlling the rate and shape of fluid flow are U.S. Pat. No. 2,303,922 issued to Frazer on Dec. 1, 1942, U.S. Pat. No. 3,129,894 issued to Schermerhorn on Apr. 21, 1964, and U.S. Pat. No. 4,869,432 issued to Jubert on Sep. 26, 1989. The Frazer patent discloses an injector nozzle having a converging portion ending at an outlet. When the pressure of the fluid inside the nozzle increases, the walls of the converging portion push outward, thus increasing the size of the outlet. As the size of the opening of the outlet is directly related to the pressure of the fluid inside the nozzle, the velocity of the fluid issuing from the outlet is maintained at a substantially constant rate.
The Schermerhorn patent shows a nozzle permitting variably restrictive flow from a faucet spout. This nozzle includes a tubular inlet portion and a progressively restricted tubular outlet portion terminating in a slit. A guard, movable about the outside surface of the nozzle, may be positioned to narrow the portion of the nozzle through which the fluid is discharged. The various positions of this guard determine the flow rate.
The nozzle described in the Jubert patent is for placement in a hydraulic or pneumatic system. The outlet dimensions of this nozzle deviate according to the pressure differential between the nozzle inlet and the nozzle outlet. One embodiment of this invention incorporates a generally flat surface positioned across the diameter of a pipe. Three slits in this generally flat surface form two displaceable tongues which allow fluid to exit the pipe. When observed from a top plan view, the slits in this generally flat surface form an "H" shape wherein the two tongues are opposite one another.
Patents pertaining to the termination or cutting-off of dispensing from a tube or similar device are U.S. Pat. No. 2,507,248 issued to Swart on May 9, 1950, U.S. Pat. No. 3,825,157 issued to Herzig on Jul. 23, 1974, U.S. Pat. No. 4,109,836 issued to Falarde on Aug. 29, 1978, and U.S. Pat. No. 4,513,891 issued to Hain on Apr. 30, 1985.
The Swart patent discloses a nozzle for a flexible tube having a U-shaped slit formed at one of the sides of the nozzle tip. This slit forms a tongue having one end displaceable from the surface of the nozzle when pressures of the fluid inside the nozzle increase upon squeezing the walls of the tube. When the squeezing of these walls is terminated, the fluid inside the nozzle no longer exerts pressure against the tongue. Therefore, displacement of the tongue from the surface of the nozzle is terminated.
The manner in which the flow of fluid is cut off form the nozzles disclosed in the Herzig the Falarde patents is similar to the manner described in the Swart patent. Although the Herzig and Falarde patents do not use tongues as disclosed in Swart, they do incorporate slits which open and close in relation to the strength of the fluid pressure against the nozzle tip. The nozzles described in both of these patents include tapered necks terminating in the slits.
The Hain patent discloses a spray dispensing container for use in the administration of nasal sprays. The spray bottle includes a spray nozzle fitted into a closure cap. The closure cap, which has a central opening for receiving the spray nozzle, has walls removably attached to the neck of the bottle. A series of air inlets arranged about the closure cap permit the bottle to return to its original shape after squeezing.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.